I didn't read the wiki about power kernel but AFAIK all the profiles and xlv should add 125 Mhz to the avoided frequencies. If this doesn't work then I'm not up-to-date. I've found my fix during my studies with my tune-up scripts. it's because the phone-app wants to write this 125 mhz frequency into min scaling. The fix can only work if 125 Mhz isn't already written in min scaling. Hence u can check it with cat first:

cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq

and then write-protect:

chmod 444 /sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq

Also u have to repeat this at startup and also I don't do phone app very much so I can't help u but the fix should work! Also in Linux when a command is succesful u don't get a feedback. I don't know what this is called! Also xlv is just an undervolting profile. It didn't work for me it is dependent of ur device i for myself use the default profile and 950 Mhz!